Most of my pinhole cameras have curved surfaces, and I started using pearl and semi-matte paper negatives in those to reduce reflections. Over time, I found that I like the texture that shows in a contact print from the pearl surface, but I think many people prefer to use glossy paper negatives for increased sharpness in contact prints too. I can definitely imaging that the texture could make a difference in a reflective enlargement!

I do not have a lot of experience contact printing glossy paper, but the times I've tried it (wet) I also had the impression that the sheets made better contact. Still, I'm not planning to switch... just got another 250 sheet box of 8x10 Adorama VC RC pearl!